The present invention relates generally to a tubular skylight assembly, and more particularly to a tubular skylight assembly with a displacement absorber and interlocking telescoping tubes.
Tubular skylights are used for transmission of outdoor, natural lighting to building interiors. Energy free and aesthetically pleasing, such devices enjoy great popularity. Tubular skylights are often installed in new construction, both residential and commercial, but also are installed as retrofitted improvements to existing residential and commercial structures.
A tubular skylight often includes an exterior dome upon the roof of a building, translucent or transparent. Light received by the dome is transmitted through light tubes to the interior of the building. The light tubes are disposed through the space between the exterior roof and the interior building ceiling. At the interior building ceiling, the transmitted light is passed through an interior light diffuser.
With more experience in the installation of tubular skylights, several problems have come to be identified. In no particular order of priority, a first problem arises from recognition that different dimensions exist in different buildings between the exterior roof and the interior ceiling, and that those dimensions may vary greatly. Moreover, even as to a particular structure, different dimensions exist between the roof and ceiling depending upon placement of the exterior dome upon the roof relative to placement of the diffuser on the interior ceiling. Economy in manufacture urges that standardization of the light tunnels would be desirable, yet a single length of light tunnel, or even a limited series of standardized lengths, cannot account for the virtually infinite variations encountered in the field. It would be desirable to have a skylight system with a light tunnel assembly that could be finely adjusted to meet the dimensions of any particular installation without requiring cutting of the light tunnel in the field or cumbersome manipulation of components. At the same time, it would be further desirable that any installation of such apparatus meeting the foregoing concerns also be as simple and foolproof as possible so as to prevent mis-assembly, mistakes, and so forth. Finally, any skylight system meeting all of the foregoing concerns also, desirably, should be inexpensive to manufacture, efficiently shippable, and easy to install.
Another problem is caused by the fact that buildings in which such tubular skylights are to be installed often have pitched roofs. While the pitch of building roofs usually is at one of only several standard gradients, the angle at which the light tunnels beneath such a roof must traverse to reach the interior diffuser panel can vary infinitely. While several devices that have already been commercialized purport to depict a straightforward and simple alignment between the exterior dome and the interior diffuser panel, experience in the field teaches that precise measurement, good alignment, and efficient light transmission can be difficult to achieve with such devices. It would be desirable, therefore, to have a skylight assembly that would allow simple yet effective fine tuning in the field of the angular orientation of the light tunnel.
Still further, it has come to be recognized that some tradesmen installing tubular skylights often prefer to assemble and install as much of a skylight system as possible from the building roof, and concomitantly to minimize the amount of time and assembly required from indoors. Reasons for this preference are varying, but include concern that indoor work in retrofitting efforts to existing buildings is intrusive to building occupants, may be crowded with other tradesmen engaged in other tasks in new construction installations, risks collateral damage from tools, ladders, and the like to interior, fine-finished surfaces such as floors and walls, and so forth. Because those who install tubular skylights often view as better devices that can be more completely assembled and installed from the outside, it would be desirable to have a skylight system that allows for the assembly and installation of as much of a skylight system as possible from the exterior building roof.
A fourth problem has been discovered with specific reference to installation of tubular skylights in new construction. Particularly, it is often desirable to be able to install a tubular skylight before the finished interior ceiling is installed. Such a desire might stem from the increased latitude provided with the scheduling and coordination of the various tradesmen involved in new construction. Moreover, installation of the skylight assembly before installation of the finished ceiling allows for more ready and efficient inspection by governmental authorities monitoring code compliance. Some attention to this concern is noted in U.S. Pat. No. 5,896,713, which contemplates attachment of a support ring to a ceiling joist prior to installation of ceiling drywall. However, the device in the '713 patent requires, at a minimum, installation of the tubular skylight after installation of the ceiling joist, and makes no allowance for installations in buildings having no ceiling joists. It would be more desirable, therefore, to have a tubular skylight assembly that could be installed after construction only of the building roof and before construction or installation of any ceiling structure or components. Such would be desirable, for example, as to installation in which ceiling joists are not ever to be installed, for example with the use of suspended tile ceilings.
Three other problems have been identified with reference to existing tubular skylight systems, and these three problems do not relate to the method or timing of installation but instead to the function and continued integrity of the skylight after installation. First, governmental authorities in some jurisdictions have enacted building code requirements that require devices such as tubular skylights to withstand certain earthquake forces. For example, one such requirement for a tubular skylight for use with the suspended ceiling requires that the tubular skylight assembly remain affixed to the roof structure of a building even if the suspended ceiling collapses as a result of earthquake forces. Skylight assemblies in which the light tubes or other components are supported by the ceiling cannot satisfactorily meet such requirements. It would be desirable to have a skylight assembly the components of which are carried by the roof of the building rather than by the ceiling.
A second functional problem has been discovered with regard to thermal expansion and contraction of the skylight assembly and/or the building in which the assembly is installed. Various components of the building and/or the skylight assembly may expand or contract thermally at different rates. Moreover, mechanical compression of an installed skylight assembly may result from workers upon the roof of a building, the weight of whom may tend to deflect the roof downward. Both the structural integrity and the aesthetic appeal of the skylight system should be preserved in either event. Thermal expansion of the skylight assembly, or compression of the roof sheathing by workers upon the roof, might cause the diffuser panel at the interior ceiling to protrude from the plane in the ceiling, or may break loose attached components of the skylight assembly, either result being undesirable. Alternatively, either effect may cause the structure of the exterior dome to protrude upward from its installed position upon the roof, breaking loose weatherproofing that would otherwise seal the installed assembly. It would be desirable, therefore, to have a skylight assembly that absorbs thermal expansion and contraction, and mechanical compression, while preserving weatherproofing, structural integrity, and aesthetic appeal of the assembly.
Finally, another problem has been encountered with the use of tubular skylights in applications in which a rectangular diffuser panel is used at the interior ceiling, such as with a suspended ceiling. It is known that light tubes of generally circular cross-section are most efficient in transmitting light from the exterior dome to the interior diffuser panel. However, adapting from such a generally circular cross-sectional light tunnel to a rectangular diffuser panel has been found to cause differential lighting upon the diffuser panel. Sometimes known as “hot spots,” in such applications the diffuser panel tends to have regions of greater light intensity and regions of lesser light intensity, a phenomenon considered to be undesirable by the consuming public. Rather, it would be desirable in such applications to provide an adaptor member between the generally circular cross-sectional light tunnel and the rectangular diffuser panel that provides a more pleasing and even distribution of light upon the diffuser panel.
The present invention relates to a new skylight assembly that provides distinct advantages of the conventional systems and methods.